Smart cards typically consist of pocket-sized, or smaller, cards with embedded integrated circuits. Memory cards and microprocessor cards are two categories of smart cards. Memory cards contain only non-volatile memory storage components. Microprocessor cards contain memory storage components and microprocessor components. Microprocessor smart cards are typically used with mobile devices, such as cellular telephones, and have both limited memory capacity and processing power relative to the memory and microprocessor contained in the mobile devices into which the smart cards are inserted.
Subscriber Identity Module (SIM), Universal Integrated Circuit Cards (UICCs), and Removable User Identity Module (R-UIM) cards are examples of microprocessor smart cards. SIM cards securely store an identifier or key used to identify a subscriber on mobile telephone devices (e.g., cellular radiotelephones). SIM cards enable users to change phones by removing the SIM card from one telephony device and inserting it into another telephony device. UICCs are smart cards used in mobile terminals in Global System for Mobile Communications (GSM) and Universal Mobile Telecommunications System (UMTS) networks. UICCs ensure the integrity and security of different types of personal data, and may include several applications that permit access to both GSM and UMTS networks. R-UIMs include cards having features that are usable with Code Division Multiple Access (CDMA), GSM and UMTS devices.